Air conditioner with temperature controlling means utilizing aspirated air

ABSTRACT

THE INVENTION PROVIDES AN AIR CONDITIONING UNIT WHERE TEMPERATURE CONTROL OF THE UNIT IS OBTAINED BY THE USE OF ASPIRATED ROOM AIR MOVING ACROSS A THERMOSTAT THAT SENSES ROOM TEMPERATURE AND FROM IT CONTROLS THE OPERATION OF THE AIR CONDITIONING UNIT. THE NEEDED ASPIRATION OF ROOM AIR OCCURS BECAUSE IT IS INDUCED BY THE LARGE AMOUNT OF RETURN AIR TAKEN FROM THE ROOM, PASSED THROUGH THE EVAP-   ORATOR COOLING COILS AND THEN RETURNED TO THE ROOM. THE ASPIRATED AIR ALSO MOVES ACROSS THE EVAPORATOR COILS SO THAT THE CAPACITY OF THE AIR CONDITIONING UNIT IS NOT REDUCED BY A BY-PASS OF THE PORTION OF THE ROOM AIR UTILIZED FOR TEMPERATURE SENSING.

Nov. 30, 1971 R. A. SHANNER 3,

AIR CONDITIONER WITH TEMPERATURE CONTROLLING MEANS UTILIZING ASPIRATED AIR 2 shG8t3..sh 1

Filed March 6, 1.970

mm Tn N n E0 V h N S A r e g 0 Dn W|TNESSES NOV. 30, 1971 SHANNER 3,623,335

AIR CONDITIONER WITH TEMPERATURE CONTROLLING MEANS UTILIZING ASPIRATED AIR Filed March 6, 1970 3 Sheets-Sheet 3 FIG. 2

United States Patent O 3,623,335 AIR CONDITIONER WITH TEMPERATURE CON- TROLLING MEANS UTILIZING ASPIRATED AIR Roger A. Shanner, Columbus, Ohio, assignor to Westinghouse Electric Corporation, Pittsburgh, Pa. Filed Mar. 6, 1970, Ser. No. 17,134 Int. Cl. F2511 17/00 US. Cl. 62-180 9 Claims ABSTRACT OF THE DISCLOSURE The invention provides an air conditioning unit where temperature control of the unit is obtained by the use of aspirated room air moving across a thermostat that senses room temperature and from it controls the operation of the air conditioning unit. The needed aspiration of room air occurs because it is induced by the large amount of return air taken from the room, passed through the evaporator cooling coils and then returned to the room. The aspirated air also moves across the evaporator coils so that the capacity of the air conditioning unit is not reduced by a by-pass of that portion of the room air utilized for temperature sensing.

BACKGROUND OF THE INVENTION Field of the invention This invention relates generally to room air conditioners and, more particularly, to a temperature control arrangement for a room air conditioner using aspirated air for temperature control.

Description of the prior art Sensing the temperature of return air from a space being conditioned with a thermostat to control the operation of the air conditioning unit is well known. The sensing may be of the main air stream, or may take place in a by-pass stream such as is shown in US. Pat. 3,194,027 issued July 13, 1965, and owned by a common assignee and US. Pat. 3,293,875 issued Dec. 27, 1966 and owned by a common assignee. In both by-pass arrangements, the quantity of return air needed for temperature sensing is passed through a control compartment for thermostatic sensing and then returned to the room without having been exposed in heat exchange relationship with the air conditioner evaporator cooling cool. The by-passed air constitutes a loss in cooling capacity that tends to place a limit on the total capacity provided by the air conditioning unit below that which would be expected. Furthermore. in the by-pass system in a draw-through unit, as the filter becomes dirty, the portion of room air drawn in by-pass increases, reducing the theoretical and actual capacity of the air conditioning unit even more.

Another disadvantage of some non-aspirated air conditioning arrangements is that a box-like configuration must be utilized for disposition of the thermostat control so the air sampled by it is sufiiciently confined around the thermostat control to insure proper response of it. In the instant aspirated air temperature sensing system, the aspirated air is drawn across the thermostat insuring proper contact without the use of a special compartment construction for it.

SUMMARY OF THE INVENTION The instant invention contemplates the use of an air conditioning configuration commonly known as a blowthrough system in conjunction with aspirated air for temperature control. In this system, the return air from the conditioned space is first drawn into and then expelled from an air mover such as fan or the like through a duct or plenum before the return air has been engaged in a heat exchanger relationship with the evaporative cooling coil. The air is then discharged from the evaporative cooling coil into the conditioned space. A thermostat is contained within the air conditioner and is suitably secured to it with an air intake passageway for it provided from the room air side into the air conditioning unit and a corresponding air exit passageway provided through a divider panel opening forwardly of the intake orifice of the air mover or fan. The major portion of return air from the room passes into the air conditioning unit through a main entrance adjacent the aforementioned air exit passageway then moves through the intake plenum and fan proper, for discharge through the evaporative cooling coil back into the room. As this main flow of room air passes across the outlet of the air exit passageway or discharge slot it causes an aspiration of air from this slot and thereby provides a room air flow across the thermostat for temperature control of the air conditioning unit. The aspirated air then joins the main stream of air flowing into the intake plenum of the fan so that no reduction of capacity of the unit is occasioned by the use of a temperature control regulated by room air temperature conditions.

DRAWING DESCRIPTION FIG. 1 is a perspective view of one embodiment of an air conditioning unit utilizing my inventive concepts, with portions broken away to show the operating components thereof;

FIG. 2 is a perspective view of a dividing panel of a second embodiment of this invention;

FIG. 3 is a somewhat schematic showing of the dividing panel of FIG. 2 incorporated in an air conditioning unit;

FIG. 4 is a perspective view of a dividing panel and included baffiing of a third embodiment of the invention;

FIG. 5 is a view similar to FIG. 3 but showing the dividing panel and included baffiing of the third embodiment of the invention;

FIG. 6 is a perspective view of the dividing panel and a channel arrangement of the fourth embodiment of the invention; and

FIG. 7 is a view of the fourth embodiment of the invention illustrated similarly to the view shown in FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION The invention will be described in connection with the accompanying drawings illustrating several embodiments of the invention that incorporate, in a room air conditioner, the principle thereof; and wherein an air conditioning unit 10 is shown in FIG. 1 which includes a boxshaped outer wrapper or housing 12 having a generally open room side face covered by a louvered front 14.

The louvered front 14 includes a room recirculating air inlet 16 on the right side of the louvered front 14 of the air conditioning unit 10 through which the room air to be conditioned passes into the air conditioner unit. The louvered front panel also includes a control face 18 disposed to the leftwardly of the air inlet 16 while an upper part of the air conditioning louver 14 (not shown) serves as a discharge means through which cooled, conditioned air is directed back into the room.

Disposed behind the room air inlet 16 in an intake orifice 20 for a fan 22 which pulls the room air through the air inlet 16. Discharge from the fan 22 takes place at discharge 24, with the air fiow directed from this discharge over a central plate 26 and then through the evaporator cooling coils 28.

The central plate 26 serves as a separator means between the upper portion of the air conditioning unit 10 in which is contained the evaporator cooling coils 28 and the lower section of the air conditioner unit in which is disposed the fan 22 and a thermostatic control and prevents cold air from being recirculated. The compartmentilization of this portion of the air conditioner unit 10 is completed by a back panel 32 which divides the air conditioning unit 10 between that portion of it disposed within the room or space to be conditioned and that portion which is outside and serves as the heat sink for the unit. A dividing panel 34 segregates the space in which the fan 22 is disposed and the space in which the thermostat control 30 and other controls (not shown) are disposed in the lower part of the air conditioning unit 10.

The thermostatic control 30 includes a bimetallic element 36 which is thermally shielded from the outer surfaces of the air conditioning unit that are subject to ambient temperatures by being mounted behind the control face 18 of louvered panel 14. The central plate 26 shields the thermostatic control from cooled air passing outwardly across the evaporator cooling coils 28. The bimetallic element is adapted to engage a switch 38 of thermostatic control 30 whenever the temperature in the room or space being air conditioned has reached or exceeded that set on the thermostatic control 39. At such time, the bimetallic element 36 will contact the switch 38 to provide a flow of current to a compressor 40 disposed behind the back panel 32 and, therefore, outwardly of the room or space being conditioned. Thus, if the room temperature set on the thermostat is exceeded by room conditions and this temperature is imposed on the thermostatic control 30, operation of the air conditioning unit 10 is controlled by it so that the compressor 40 provides refrigeration to the evaporator cooling coils 28.

In Order to permit the flow of recirculated room air across the bimetallic element 36 of the thermostat control 30, the thermostat control 30 includes a bracket means 42 which is substantially yoke shaped and conveniently attached to the front of the solid panel control face 18 so as to space the thermostatic bimetallic element 36 rearwardly of this panel. An elongated orifice 44 generally aligned with but ofiset from the thermostat control 30 but spaced leftwardly therefrom on the opposite side of the thermostatic control 30 than the fan 22 is provided in the control face 18 so as to permit a flow of air inwardly into the compartment containing the thermostat control 30. This elongated orifice may conventionally taken the shape of an elongated slot with rounded ends so as to provide a fairly streamlined opening for the flow of room air inwardly into the air conditioner unit 10. Also aligned with the thermostat control 30 but offset therefrom is an orifice 46 which provides communication between the space provided behind the control face 18 and the space rightwardly of the dividing panel 34 in which the fan 22 is disposed. This orifice takes the form of a rectangle with the elongated portion of the rectangle extending upwardly and downwardly relative to the dividing panel 34. Because of the location of the fan 22 and its inlet orifice 20, air is pulled or drawn from the room through the air inlet 16 to pass through the fan.

At the same time, this major return air flow passes across the orifice 46 in the dividing panel 34, causing a consequent aspiration of air inwardly into the main air fiow from the compartment dis-posed leftwardly of the dividing panel 34 and into the area of the fan inlet orifice 20. This air then passes through the fan 22 and outwardly through the evaporative cooling coils 28. By the described arrangement, then, room air is provided by aspiration so as to impinge and pass across the bimetallic element 36 so that the thermostatic control 30 may read the temperature of the space being conditioned. A signal through its switch 38 actuates the compressor 40 to provide liquid refrigerant to the evaporator cooling coils 28. It is specifically pointed out that the entire flow of air across the thermostatic element 36 passes inwardly into the fan orifice area so that no room return air is by-passed and the entire flow of air passing inwardly into the air conditioning unit from the room or space being cooled then passes over the evaporative cooling coils 28 so that the full cooling capacity of the air conditioning unit 10 can be obtained.

The aspiration obtained according to the invention is distinct from the arrangement for obtaining by-pass fiow as disclosed in the noted Kelly patent. In the Kelly draw through arrangement, the same pressure drop appearing across the upstream filter and evaporator also appears across the by-pass passage and the suction induced by-pass flow results. In contrast, since in a blow-through system the evaporator is downstream from the fan, the pressure drop across the evaporator is not available across the by-pass passage. Hence, it is the aspirating effect, rather than a suction eifect, which is mainly responsible for the by-pass fiow according to the invention.

Turning now to the second embodiment (illustrated in FIGS. 2 and 3) it can be seen that the air which fiows over the thermostat control 30 has a flow of air thereover which enters the inlet orifice of the fan 22 of air conditioning unit 10 by means of the elongated orifice 44. The dividing panel 34', in this particular embodiment, uses a series of elongated orifices 48 formed by lourvers 49 to provide for the discharge of the air from the area surrounding the thermostat control 30. Again the main fiow of air through the inlet opening 16, as provided by the fan 22, actuates a flow of air across the thermostatic control 38 through the elongated orifice 44 and then through the louvered openings 48 to provide an aspirated air flow inwardly into the air conditioning unit 10. This aspirated air, as in the first embodiment, joins the main fiow of air and is discharged from the fan through the evaporator cooling coil 23.

The embodiment shown in FIGS. 4 and 5, shows another slightly modified dividing panel 34", having a baffie 50 of general U shape disposed so as to lead the aspirated air through a rectangular aperture 52 in dividing panel 34 inwardly toward the fan 22. Again air fiows through the elongated aperture 44 and over thermostatic control 30 to be exhausted through the rectangular aperture 52 due to aspiration caused by the main fiow of air passing across the discharge end of the bafile 50. This air then passes into the room through evaporative coils 22.

FIGS. 6 and 7 show a fourth embodiment of the invention and in which a conduit member 54 is utilized for leading the aspirated air rearwardly toward the fan 22 from its passage over thermostatic control 30. The conduit member 54 has a substantially right angled bend therein, but this bend is gradual so as to be streamlined to prevent the obstruction of air flow through it. A discharge 58 provided for the conduit member has the plane of its opening substantially perpendicular to the main air flow. Again this flow is inwardly through the inlet 16 and through the fan 22, with the aspirated air flowing inwardly through the elongated aperture 44 across the thermostatic control 30 and then through the conduit member 54 so as to be discharged adjacent to the fan 22. The conduit is generally square in cross section tapering slightly towards its discharge end 58 in the horizontal direction so that this end of the conduit member is rectangular while its inlet end mates with a nearly square aperture 56 formed in the divider panel 34.

It should be clear that, although only four embodiments of the invention have been disclosed, many modifications can be made to the invention to provide an aspirated air flow over a thermostatic control means, with this aspirated air flow joining the main flow of air to be directed by a fan through an air conditioner evaporates cooling coils so that no reduction in refrigerant capacity of the air conditioning unit is occasioned by controlling the air conditioning unit by room return air. Further, it

should be clear that the thermostatic control 30 could be utilized to control a heating means or could be replaced by a humidity sensitive element and the humidity of the conditioned space then be utilized to control the operation of the air conditioning unit.

What is claimed is:

1. An air conditioning unit including:

(a) a housing,

(b) a main inlet means opening into said housing,

(c) a fan means disposed behind said inlet means,

(d) an aperture means formed in said housing,

(e) a control means disposed adjacent to said aperture means inwardly in said housing,

(f) a dividing panel means disposed between said control means and said fan means for providing at least a pair of compartments in said housing,

(g) an air exit means disposed adjacent to said control means and in said dividing panel means, said air exit means being disposed upstream from said fan means for providing a flow of aspirated air through said aperture means and said air exit means to provide a flow of room air over said control to control the operation of said air conditioning unit.

2. The air conditioning unit of claim 1 wherein air cooling means is disposed downstream from said air exit means and said main inlet means.

3. The air conditioning unit of claim 3 wherein panel means separates said air cooling means from said control means.

4. The air conditioning unit of claim 3 wherein said air exit means comprises an elongated aperture means,

5. The air conditioning unit of claim 4 wherein said elongated aperture means comprises a single elongated rectangular opening in said dividing panel means, opening without impedance to the main stream of flow of air created by said fan means.

6. An air conditioning unit including:

(a) a main flow inducing means for moving air from a space being conditioned,

(b) an aperture means disposed adjacent to said main flow inducing means,

(c) a thermostat control means mounted adjacent said aperture means,

(d) said aperture means being disposed upstream from said main flow inducing means whereby movement of air flow by said main flow inducing means induces by aspiration a secondary flow through said aperture means from said space being conditioned to provide space temperature air to said thermostatic control, and

(e) cooling coil means disposed downstream from said main flow inducing means and downstream from said aperture means whereby the total return air flow to said air conditioner passes over said cooling coil means.

7. An air conditioning unit including:

(a) a housing,

(b) a main inlet means opening into said housing,

() a fan means disposed behind said inlet means,

(d) an aperture means formed in said housing,

(e) a control means disposed adjacent to said aperture means inwardly in said housing,

(f) a dividing panel means disposed between said control means and said fan means for providing at least a pair of compartments in said housing,

g) an air exit means disposed adjacent to said control means and in said dividing panel means, said air exit means being disposed upstream from said fan means for providing a flow of aspirated air through said aperture means and said air exit means to pro- .vide a flow of room air over said control means to control the operation of said air conditioning unit,

(h) air cooling means disposed downstream from said fan means,

(i) panel means separating said air cooling means from said control means,

(j) said air exit means comprising an elongated aperture means,

(k) said elongated aperture means formed by a series of louvered openings in said dividing panel means.

8. An air conditioning unit including:

(a) a housing,

(b) a main inlet means opening into said housing,

(c) a fan means disposed behind said inlet means,

(d) an aperture means formed in said housing,

(e) a control means disposed adjacent to said aperture means inwardly in said housing,

(f) a dividing panel means disposed between said control means and said fan means for providing at least a pair of compartments in said housing,

(g) an air exit means disposed adjacent to said control means and in said dividing panel means, said air exit means being disposed upstream from said fan means for providing a flow of aspirated air through said aperture means and said air exit means to provied a flow of room air over said control means to control the operation of said air conditioning unit,

(h) air cooling means disposed downstream from said fan means,

(i) panel means separating said air cooling means from said control means,

(j) said air exit means comprising an elongated aperture means,

(k) said elongated aperture means having disposed outwardly therefrom a U-shaped baffie attached to said dividing panel means.

9. An air conditioning unit including:

(a) a housing,

(b) a main inlet means opening into said housing,

(c) a fan means disposed behind said inlet means,

(d) an aperture means formed in said housing,

(e) a control means disposed adjacent to said aperture means inwardly in said housing,

(f) a dividing panel means disposed between said control means and said fan means for providing at least a pair of compartments in said housing,

(5) an air exit means disposed adjacent to said control means and in said dividing panel means, said air exit means being disposed upstream from said fan means for providing a flow of aspirated air through said aperture means and said air exit means to provide a flow of room air over said control means to control the operation of said air conditioning unit,

(h) air cooling means disposed downstream from said fan means,

(i) panel means separating said air cooling means from said control means,

(j) said air exit means comprising an elongated aperture means,

(k) said elongated aperature means having disposed outwardly therefrom a fully walled conduit means exiting adjacent said fan means.

References Cited UNITED STATES PATENTS MEYER PERLIN, Primary Examiner U.S. Cl. X.R. 62229, 262 

